The present invention relates to fuel assemblies in which a fuel rail and an air manifold are preassembled a predetermined distance apart from each other, and then fuel injectors are installed in the fuel rail and the air manifold.
In an internal combustion engine, fuel injectors are used to provide precisely metered amounts of fuel to a combustion air supply for combustion. For a typical top feed fuel injector, the fuel is provided to the fuel injector from a fuel rail connected to one end of the injector, typically called the fuel inlet. The fuel injector meters the fuel from a distal end of the injector, typically called the injector tip. The fuel is metered into an air intake manifold, where the fuel mixes with the combustion air prior to its introduction into the combustion chamber.
In a typical top feed injector fuel rail installation, the fuel rail engages the fuel inlet of the fuel injector in a fuel cup, which surrounds the inlet tube of the fuel injector. The fuel cup/fuel inlet interface is made leak-proof through the use of a seal, typically an o-ring installed on the injector. A retaining device, such as a clip, secures each injector in place in its respective rail cup.
In some installations, a need exists for the injector spray to be precisely positioned in reference to the engine components. This is usually done in the installation by incorporating an anti-rotating device that can be part of the function of the retaining device.
At the discharge end of the injector, the injector tip is inserted into the air intake manifold by engaging each fuel injector into a corresponding intake air manifold pocket. The pocket/injector tip interface is typically sealed with a seal, such as an o-ring mounted on the fuel injector. Once the assembly is installed, the rail is securely connected to the air intake manifold, such as by welding, bolting, or other known connection method. The fuel injectors are held between the fuel rail and the air intake manifold, with little or no axial play for the fuel injector.
An integrated fuel rail/air intake manifold, where the fuel rail is connected to the air intake manifold by molding the fuel rail with the air intake manifold, or by welding, bolting, or otherwise connecting the fuel rail to the air intake manifold, requires the connection of the fuel rail and air intake manifold prior to the insertion of the fuel injectors. Such a design has several advantages, including a lower cost of an integrated fuel rail/air intake manifold as compared to two separate components, a better mounting location of the fuel rail on the air intake manifold for better protection from impact, and a lower installation cost as compared to installing separate components.
However, to provide such an integrated fuel rail/air intake manifold assembly, the distance between the injector cup on the fuel rail and the air intake manifold pocket is shorter than the length of the fuel injector. It would be beneficial to provide a configuration of an integrated fuel rail/air intake manifold assembly with fuel injectors which enables installation of the fuel injectors into the assembly.
Briefly, the present invention provides a fuel assembly comprising a fuel supply conduit, an air intake manifold, a fuel injector, and a spacer. The air intake manifold is disposed a predetermined distance from the fuel supply conduit. The fuel injector has a first end disposed in the fuel supply conduit and a second end disposed in the air intake manifold. The fuel injector has a length greater than the predetermined distance. The spacer is disposed about a portion of the fuel injector such that the spacer retains the first end of the fuel injector in the fuel supply conduit and the second end of the fuel injector in the air intake manifold.
A clip for connecting a fuel injector to one of a fuel cup and an air intake manifold is also provided. The clip comprises a generally C-shaped body portion having a first body end, a second body end biased toward the first end, and a longitudinal axis extending therethrough. The clip also comprises a generally C-shaped upper sleeve extending generally perpendicular to the longitudinal axis. The upper sleeve has a first upper sleeve end and a second upper sleeve end biased toward the first upper sleeve end. An upper connector connects the upper sleeve to the body portion. The clip further comprises a generally C-shaped lower sleeve extending generally parallel to the upper sleeve. The lower sleeve has a first lower sleeve end and a second lower sleeve end biased toward the first lower sleeve end. A lower connector connects the lower sleeve to a distal end of the body portion.
A method of installing a fuel injector into a fuel supply conduit and an air intake manifold is also provided. The fuel supply conduit is disposed along an axis a predetermined distance from the air intake manifold. The method comprises inserting a first end of the fuel injector into one of the fuel supply conduit and the air intake manifold at an angle oblique to the longitudinal axis; displacing the injector toward the one of the fuel supply conduit and the air intake manifold until a second end of the fuel injector clears the other of the fuel supply conduit and the air intake manifold; pivoting the fuel injector about the first end until the fuel injector is aligned with the longitudinal axis; and displacing the injector toward the other of the fuel supply conduit and the air intake manifold until the second end of the fuel injector engages the other of the fuel supply conduit and the air intake manifold.
Also, a method of removing a fuel injector from a fuel supply conduit and an air intake manifold is provided. The fuel supply conduit is disposed along an axis a predetermined distance from the air intake manifold. The fuel injector has a first end engaged with one of the fuel supply conduit and the air intake manifold and has a second end engaged with the other of the fuel supply conduit and the air intake manifold. The method comprises displacing the fuel injector along the axis such that the first end of the fuel injector is disengaged from one of the fuel supply conduit and the air intake manifold; pivoting the fuel injector about the second end such that the first end clears the one of the fuel supply conduit and the air intake manifold; displacing the fuel injector generally along the axis such that the second end of the fuel injector is disengaged from the other of the fuel supply conduit and the air intake manifold; and removing the second end from the other of the fuel supply conduit and the air intake manifold.